Other Parts Discussed in Thread: TPS65988, BQ25703A
Hi Team.
One of my customers is working a new design which is basically a tablet that will have USB –C as the only method of charging. I gave them http://www.ti.com/tool/TIDA-01627 reference design as a first pass and they are very interested in the TPS65987D.
The device they are building will require about 10-15hA of 1 cell lithium batteries, whether they are in series or parallel isn’t a requirement. The load will be 3.3V and 5V. looks like TPS6598x device supports both PD and BC12 which is an important feature for them so this product can support existing legacy hardware. This device will only ever present as a sink on its USB –C port which is for charging and USB2 communication with PC host. The design requires both high power charging (30W) through this port (thus requires PD) and at least 15W charging through legacy systems like USB-A power supplies and USB-A parts on typical PC.
I’ve sent them a lot of material already such as how to implement I2C master in these controllers - http://www.ti.com/lit/an/slvae18/slvae18.pdf and http://www.ti.com/tool/tps6598x-config but they cannot find EEPROM files used by these boards – do we have them available ?
In the application configuration software, they cannot access any I2C master settings when selecting the TPS65987D IC, only the dual port TPS65988 IC. Are the configuration files the same? Can they use the TPS65988 settings and simply ignore the second port?
If that’s not possible, They are thinking they might end up using TPS65988 (dual port) and just add a barrel jack alongside the USB-C port s users can plug their device into a legacy USB2 port for communication while still charging the device via a barrel jack. TPS65988 offers logic and switches for two sink paths, with reverse current protection, OVP, break-before-make, and dead battery support from both ports, eliminating several other protection and ORing components.
Do you see any potential issues with using a “dumb” barrel jack as one of the VBUS inputs to TPS65988? The SLVA994 document mentions compatibility with chargers that provide high voltage without correct PD negotiation.
Lastly, BC1.2 is mentioned in some of these documents but there are no settings in the application configuration software that I can find, no registers or events etc. There is a document I found related to BQ25703A that explains its Input Current Optimizer ( http://www.ti.com/lit/an/slva812a/slva812a.pdf ), but it still requires some configuration from I2C master. Is there an app note on implementing BC1.2 and/or >1.5A charging on legacy hardware?
Thank you for your help!
Regards,
Dmitry
